Half-Hourly Metering: The Mandatory Changes Your Business Isn’t Ready For

Most businesses are still operating under outdated electricity billing assumptions—and they’re about to pay the price. Half-hourly metering isn’t coming someday; it’s arriving with hard deadlines and real financial consequences. Your competitors might already be adapting their energy strategies around 30-minute consumption data and time-of-use tariffs, whilst you’re still working with yesterday’s information. The businesses that move now will control their costs; the ones that wait will scramble. Here’s what you actually need to know before the rules change.

What Is Half-Hourly Settlement and Why Does It Matter Now?

If you’ve been paying your electricity bills based on estimates, those days are numbered. Market-Wide Half-Hourly Settlement (MHHS) is Ofgem’s mandatory reform kicking off October 2025. The gist? Your smart metre will transmit usage data every 30 minutes. No more guesswork.

Here’s the thing. The current system relies on profiles and monthly readings. Suppliers don’t actually know *when* you’re using power. Just how much. That’s wildly inefficient.

MHHS changes everything. Half-hourly data enables precise demand forecasting, which helps balance the grid. It also supports smart charging for EVs and makes renewable integration actually work. This precision ensures that customer bills accurately reflect actual consumption rather than estimated averages. With advanced energy monitoring tools, businesses can leverage this granular data to identify peak usage periods and optimise their consumption patterns accordingly. Establishing data insights from half-hourly metering allows organisations to benchmark performance against industry standards and uncover hidden optimisation opportunities.

Why now? The UK’s pushing towards net zero. And frankly, the old system couldn’t keep up. This reform gives everyone the data accuracy needed to get there. Ofgem estimates the programme will deliver net benefits of £1.6 billion to £4.5 billion to consumers in Great Britain from 2021 to 2045.

Key Deadlines Your Business Must Meet Before December 2026

Look, these dates aren’t suggestions. They’re regulatory requirements backed by Ofgem. Your supplier’s scrambling to get systems ready. You should probably know what’s coming your way too. The full transition wraps up by May 2027, when all metres must be migrated to half-hourly settlement. If your supplier fails to qualify by the late October 2026 deadline, they’ll be barred from signing up new customers until they do. A structured compliance audit can help identify any gaps in your current metering systems before these deadlines arrive. Enerbiz can help you navigate these changes by providing bill validation post-switch to ensure your supplier is implementing the new metering requirements correctly.

How Half-Hourly Data Will Change What You Pay

The way you pay for electricity is about to get a serious wake-up call. Those estimated bills? Gone. Half-hourly metering records your actual consumption every 30 minutes. No more guessing games.

Here’s the thing. Your costs could go up or down. It depends entirely on *when* you’re using power. Businesses that run heavy during peak hours might see bills climb. Those operating off-peak? Potentially cheaper rates. With real-time data capture, you’ll have unprecedented visibility into your consumption patterns throughout the day.

The tariff complexity is real, folks. Suppliers can now offer time-of-use pricing based on your actual data. That means behavioural changes in your operation directly impact what you pay. Strategic contract negotiation can help you secure terms that work with your usage patterns.

Some modest metering charges might pop up too. Usually small stuff, often baked into standing charges already. Nothing earth-shattering.

How Time-of-Use Tariffs Create New Costs and Savings

Time-of-use tariffs are basically a double-edged sword for your business. If you can’t shift your energy usage away from peak periods, you’re looking at cost increases of 7% to 11%—ouch.

But here’s the flip side: businesses that play the game right and move consumption to off-peak hours are saving an average of £188 per year, with some cutting peak usage by 28%. Understanding your consumption patterns through advanced monitoring systems gives you the visibility needed to identify which operations can be scheduled during cheaper hours and maximise those savings. Implementing customised reduction strategies tailored to your unique business needs ensures you can capitalise on these time-of-use opportunities effectively.

Peak Pricing Risk Factors

Price volatility has exploded. Risk premiums have ballooned over the past 18 months thanks to shifting energy policies, AI-driven demand growth, and grid reliability concerns. Supply constraints from weather interruptions or global events? Those hit your bill directly now.

Here’s what’s driving peak pricing risks:

1. Extreme weather events cause demand spikes that send prices soaring—think heatwaves maxing out air conditioning or cold snaps crushing the grid.
2. Fuel price fluctuations in natural gas, coal, and oil translate straight into your peak period rates.
3. Infrastructure upgrades and new regulatory costs get baked into those premium time slots. Aligning your energy management with ISO standards helps document and track these cost pressures systematically.

Implementing real-time monitoring tools across your energy systems enables you to identify consumption patterns during peak periods and adjust operations accordingly to mitigate these cost impacts.

Welcome to the club. It’s expensive here.

Off-Peak Savings Opportunities

Shifting your energy use to off-peak hours actually works. Data shows 95% of businesses on time-of-use tariffs paid equal or less than the cheapest fixed-price alternatives. That’s not marketing spin.

The maths is simple. Peak hours (4 p.m. to 9 p.m.) cost more. Off-peak hours (9 p.m. to 6 a.m.) cost way less. You’re part of a growing group of businesses figuring this out.

Process automation lets your equipment run during cheap windows without anyone babysitting it. Thermal storage systems bank that off-peak energy for later use. Manufacturing facilities running overnight? They’re grabbing lower per-unit charges.

Electric vehicle owners saw 47% peak consumption drops. Monthly carbon savings hit 4.5 kilograms per engaged user. Real numbers. Real impact.

What If Your Supplier Isn’t Ready for Half-Hourly Settlement?

If your energy supplier hasn’t prepared for half-hourly settlement, you’re about to feel the consequences. Supplier readiness isn’t just their problem—it becomes yours. Fast.

Supplier readiness isn’t just their problem—it becomes yours the moment they miss the deadline.

Here’s what happens when suppliers fail to meet the M14 deadline in late October 2026:

1. They can’t acquire new customers. That’s right. Banned from growing their business entirely.
2. Customer retention gets messy. Suppliers scrambling to catch up often drop the ball on service.
3. You’re stuck in limbo. Billing errors, settlement issues, and data processing failures? All possible.

The testing and approval process takes up to 14 months. That’s not a typo. Suppliers who haven’t started are already behind.

Meanwhile, prepared competitors are grabbing market share. Guess who’s left holding the bag?

Does Your Business Need a New Metre Under MHHS?

So your supplier’s ready. But what about your metre?

Here’s the deal. If your business hits 100 KVA peak demand during any half-hour period, you’re getting a new metre. No debate. No wiggle room. It’s mandatory.

Running between 70 and 100 KVA? You’ve got options. Metre upgrades aren’t required, but plenty of businesses in your position choose them anyway. Why? Those consumption understandings are genuinely useful.

Moving premises soon? Check for “00” next to the S on your existing metre. That tells you what you’re working with.

Already have a SMART or AMR metre? Good news—it’ll keep functioning. Bad news—you’ll still need compatibility checks for MHHS.

And if you’re below the threshold with a traditional metre? You’re off the hook. For now.

How to Get Your Business Ready Before the 2026 Deadline

Getting your business squared away before December 2026 isn’t rocket science, but it does require actual effort.

Getting ready for December 2026 takes real work, but it’s completely doable if you start now.

Most businesses will be migrated by May 2027, but changes are already live. So yeah, the clock’s ticking.

Here’s what you’re looking at:

1. Gather your half-hourly data now — establish baseline consumption patterns and identify those pesky usage peaks
2. Contact your energy supplier — confirm their systems can handle half-hourly data collection and processing
3. Set up internal processes — integrate metre data into existing systems and get your staff training sorted

Data governance matters here.

You’ll need procedures for tracking consumption across different times of day.

Create dashboards.

Visualise the data.

Your team needs to actually grasp what they’re looking at.